Chicks just out of the brooder aren’t ready yet to greet the world, and are not ready to join an existing flock. So, there needs to be a middle ground created. This middle ground is called a Grow Out Pen, which is just a fancy name for a safe enclosure for young birds to grow up in!
The guidelines for transitioning chicks from the brooder to a grow-out pen is when the chicks are fully feathered, which is between six and eight weeks. Allow young birds to mature in a grow-out pen until they are around four or five months old.
This is important because, in the chicken world, size definitely matters. Introducing small/young birds to a mature flock is a sure ticket to a drama show, and it could be a bloody one too! Grow-out pens slowly introduce juveniles gradually to an existing flock, making the transition easier for future interaction.
You’ll want to keep your grow pen in plain view of the adult flock. They will be very curious about the youngsters for a few days and then return to business as usual. The chicks will be timid, or hide for the first few days, then will accept their onlookers as nonthreatening and return to normal behavior.
Introduce Change Slowly
The whole key to enjoying chickens is to avoid those problems that cause chaos in the chicken yard. Nothing good comes from rushing introductions or changes. The pecking order is serious business, and it’s a given that feeders, drinkers, and nest boxes have already been claimed and will be protected by an existing flock. When your juveniles are ready to join the flock, add more of those sought-after necessities so the new birds aren’t bullied.
Ready to Leave the Grow Out Pen?
No problem, the trick is to not overthink it. Your existing flock is quite used to seeing the young birds already, and the juveniles are very unlikely to make a mad dash to freedom the minute the grow-out pen door opens. It’s all a process, one that will naturally go smoothly if you let them exit the grow-out pen on their own. They’ll take a few steps out, then run back in for days, even a week. That’s fine, just close them in at night, and in the morning open the door again.
Social ranking among your chickens will begin almost immediately. Sometimes it’s hard to watch the fuzzy babies you raised all these months to get pushed around, you’ll want to intervene and protect them. My advice to you is to walk away and don’t look for problems. I guarantee, if you look for trouble you’re going to find it! The flock will work everything out on their own over time. You’ll know when you have to step in, and when to let nature take its course.
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